反相高效液相色谱法测定2，3—酸

研究采用反相高效液相色谱法，甲醇／水＝70／30为流动相，在C18柱上分离并测定2，3－酸，用紫外检测器检测，波长220nm，苯酚为内标物，内标法定量。该法操作简便、快速、准确，相对标准偏差为0．5％，回收率为99．0－101．5％。     

RT-PCR法检测庚型肝炎病毒C(GBV-C)RNA

应用RT－PCR法在非甲～非戊型肝炎患者血清及单采浆站供血员血浆中检测到GBV－CRNA，扩增产物经序列测定进一步确证，在30例非甲～非戊型肝炎患者中阳性率为6．6％；在600例单采浆供血者血浆中阳性率为0．33％。提示GBV－C可能不是非甲～非戊型肝炎的主要致病因子，可能存在GBV－C健康携带者。     

N-甲基乙酰氧基乙酰苯胺的液谱分析

本文研究了高效液相色谱测定N－甲基乙酰氧基乙酰苯胺的方法。采用Hypersil C18柱，以甲醇：水＝60：40（V／V）为流动相。该方法的变异系数为0．43％，回收率为98．9％－100．6％。     

解草唑的高效液相色谱分析方法研究

本文研究了用高效液相色谱法测定解草唑的分析方法，峰高定量，标准偏差为０．２２％，变异系数为０．２４％，回收率为９８－１０１％。     

甲氨基阿维菌素苯甲酸盐高效液相色谱分析

采用C18，色谱柱，以甲醇 乙腈 三乙胺水溶液为流动相，在245nm紫外波长下对甲氨基阿维菌素苯甲酸盐进行反相高效液相色谱分析。以外标法测定，本方法变异系数为10．5％，回收率为98．1％—100．3％，线形相关系数为0．9998，是一种快速、准确的分析方法。     

螺旋藻多糖Smith降解产物的HPLC研究

本文采用纸色谱和高效液相色谱研究了螺旋藻多糖Ｓｍｉｔｈ降解产物，经ＨＰＬＣ分析降解产物为乙二醇（２４．８２％），丙三醇（１３．３８％）和丁四醇（６１．７８％）据此可知螺旋藻多糖的糖苷键的连结方式为１，６－连结和１，４－连结，且以１，４－连结为主。     

三氯吡啶醇,三氯吡啶醇钠的高效液相色谱分析

本文介绍了用高效液相色谱测定三氯吡啶醇或三氯吡啶醇的分析方法。本法的变异系数为０．４６％，回收率为９９．２６％－１００．６７％，线性相关系数为０．９９９８％。     

汽提塔痕量铁分析方法的改进

对痕量铁分析方法进行了研究。该方法检测下限为0．5μg/L，回收率在94．6％－104．8％之间。     

碳四烯烃催化裂解制丙烯的研究

采用固定床,以1-丁烯为原料,考察了ZSM-5分子筛催化剂上反应温度对催化裂解产物的影响。实验结果表明,随反应温度的升高,乙烯产率和丙烯产率均增大,620℃时分别为15．40％和33．80％。催化裂解副产重组分中,液相产物接近90％是苯、甲苯、C8芳烃和C9芳烃。C5^=和C6产率均随反应温度升高而降低,C5^=产率下降明显,650℃时仅为2．3％。     

高效液相色谱法测定2，4—二苯基—1，5—苯并硫氮杂Zhou—α—（丁二酰亚胺基）—β—内酰胺

建立了测定2，4－二苯基－1，5－苯并硫氮杂Zhou－α-（丁二酰亚胺基）－β－内酰胺高效液相色谱法，该法线性范围在0－0．1mg/mL,加归方程为A＝196734675．7c-358432.3，相关系数r=0.9993,相对标准偏差0.38%(c=0.06mg/mL,n=5，检出限为0．06μg/mL。平均回收率在95．7％－103．9％之间。     

单体酸混合物成分的GC-MS分析

研究了生产二聚酸时得到的副产品单体酸的化学组成的GC MS分析方法,样品首先用质量浓度为140g/L KOH M eOH进行甲酯化,然后用GC MS进行分析和鉴定,共鉴定出棕榈酸、肉豆蔻酸、10甲基月桂酸、12甲基十四烷酸、十八烯酸等13种物质,总脂肪酸的质量分数占76.71%,其中饱和酸占66.36%,不饱和酸占10.35%,其中直链酸占饱和脂肪酸的41.02%,支链酸即异构酸占饱和脂肪酸的58.98%。     

Enrichment of lesquerolic and auricolic acids from hydrolyzed Lesquerella fendleri and L. gordonii oil by crystallization

Lesquerolic and auricolic acids were obtained from hydrolyzed lesquerella oil by a low-temperature crystallization procedure. The lesquerolic and auricolic fatty acid fraction was enriched from 55–59% to 85–99% with high yields (94%). Washing the free fatty acids with pH 6.0 buffer provided reproducible crystallizations of those hydroxy fatty acids. In contrast, when hydrolyzed oil from Lesquerella fendleri was not buffer-washed, there was, in most cases, no separation of hydroxy fatty acids by crystallization. This crystallization procedure is suitable for a large-scale separation process of the hydroxy fatty acids from nonhydroxy fatty acids obtained from hydrolyzed lesquerella oil.     

混合脂肪酸的分离

以一般油脂加工副产物十八碳混合脂肪酸为原料,采用配合结晶梯度冷冻反萃取分离技术,不经任何热处理以避免聚合作用的发生,使混合脂肪酸中的饱和脂肪酸与不饱和脂肪酸分离,同时将不饱和脂肪酸分成油酸和(亚油酸+亚麻酸)两组分。后者含量可达95%以上。     

以弱碱性树脂去除废水中5-氨基-2-氯苯-4-磺酸和盐酸

This research deals with an investigation of the adsorption of two acids, namely, 5-amino- 2-chlorotoluene-4-sulfonic and chlorhydric acids from their solution onto weakly basic resin. The screening of resins, kinetics, and isotherm were studied. The results indicate that the D301R is more appropriate for the removal of acids from solution. The adsorption of acids obeys Langmuir isotherm and the first-order kinetics model. Sorptive affinity of the two acids on D301R was found to be in the order of 5-amino-2-chlorotoluene-4-sulfonic acid〉 chlorhydric acid. Thermodynamic parameters for the adsorption of acids were calculated and discussed. The maximum removal of acids was observed around 97% and 76% at 25℃ for 5-amino-2-chlorotoluene-4-sulfonic acid and chlorhydric acid, respectively.     

Selectivity of lipases: isolation of fatty acids from castor,coriander, and meadowfoam oils

The lipase‐catalyzed hydrolysis of castor, coriander, and meadowfoam oils was studied in a two‐phase water/oil system. The lipases from Candida rugosa and Pseudomonas cepacia released all fatty acids from the triglycerides randomly, with the exception of castor oil. In the latter case, the P. cepacia lipase discriminated against ricinoleic acid. The lipase from Geotrichum candidum discriminated against unsaturated acids having the double bond located at the Δ‐6 (petroselinic acid in coriander oil) and Δ‐5 (meadowfoam oil) position or with a hydroxy substituent (ricinoleic acid). The expression of the selectivities of the G. candidum lipase was most pronounced in lipase‐catalyzed esterification reactions, which was exploited as part of a two‐step process to prepare highly concentrated fractions of the acids. In the first step the oils were hydrolyzed to their respective free fatty acids, in the second step a selective lipase was used to catalyze esterification of the acids with 1‐butanol. This resulted in an enrichment of the targeted acids to approximately 95—98% in the unesterified acid fractions compared to the 70—90% content in the starting acid fractions.     

Reaction mechanisms and kinetics of xylo‐oligosaccharide hydrolysis by dicarboxylic acids

Hydrothermal pretreatment of lignocellulosic materials generates a liquid stream rich in pentose sugar oligomers. Cost‐effective hydrolysis and utilization of these soluble sugar oligomers is an integral process of biofuel production. We report integrated rate equations for hydrolysis of xylo‐oligomers derived from pretreated hardwood by dicarboxylic maleic and oxalic acids. The highest xylose yield observed with dicarboxylic acids was 96%, and compared to sulfuric acid, was 5–15% higher with less xylose degradation. Dicarboxylic acids showed an inverse correlation between xylose degradation rates and acid loadings unlike sulfuric acid for which less acid results in less xylose degradation to aldehydes and humic substances. A combination of high acid and low‐temperature leads to xylose yield improvement. Hydrolysis time course data at three different acid concentrations and three temperatures between 140 and 180°C were used to develop a reaction model for the hydrolysis of xylo‐oligosaccharides to xylose by dicarboxylic acids. © 2012 American Institute of Chemical Engineers AIChE J, 59: 188–199, 2013     

Influence of Temperature on the Fatty Acid Composition of the Oil From Sunflower Genotypes Grown in Tropical Regions

The influence of temperature on the fatty acid composition of the oils from conventional and high oleic sunflower genotypes grown in tropical regions was evaluated under various environmental conditions in Brazil (from 0° S to 23° S). The amounts of the oleic, linoleic, palmitic and stearic fatty acids from the sunflower oil were determined using gas chromatography (GC). The environment exhibited little influence on the amounts of oleic and linoleic fatty acids in high oleic genotypes of sunflower. In conventional genotypes, there was broad variation in the average amounts of these two fatty acids, mainly as a function of the minimum temperature. Depending on the temperature, especially during the maturation of the seeds, the amount of oleic acid in the oil of conventional sunflower genotypes could exceed 70 %. Higher temperatures led to average increases of up to 35 % for this fatty acid. Although the minimum temperature had the strongest effect on the fatty acid composition, locations at the same latitude with different minimum temperatures displayed similar values for both oleic acid and linoleic acid. Furthermore, minimum temperature had little influence on the amounts of palmitic and stearic fatty acids in the oil.     

Concentration and purification of stearidonic,eicosapentaenoic, and docosahexaenoic acids from cod liver oil and the marine microalgaIsochrysis galbana

n-3 Polyunsaturated fatty acids (n-3 PUFA) from the marine microalgaIsochrysis galbana were concentrated and purified by a two-step process—formation of urea inclusion compounds followed by preparative high-performance liquid chromatography. These methods had been developed previously with fatty acids from cod liver oil. By the urea inclusion compounds method, a mixture that contained 94% (w/w) stearidonic (SA), eicosapentaenoic (EPA), plus docosahexaenoic (DHA) acids (4:1 urea/fatty acid ratio and 4°C crystallization final temperature) was obtained from cod liver oil fatty acids. Further purification of SA, EPA, and DHA was achieved with reverse-phase C₁₈ columns. These isolations were scaled up to a semi-preparative column. A PUFA concentrate was isolated fromI. galbana with methanol/water (80:20, w/w) or ethanol/water (70:30, w/w). With methanol/water, a 96% EPA fraction with 100% yield was obtained, as well as a 94% pure DHA fraction with a 94% yield. With ethanol/water as the mobile phase, EPA and DHA fractions obtained were 92% pure with yields of 84 and 88%, respectively.     

Profile of (n‐9) and (n‐7) Isomers of Monounsaturated Fatty Acids of Radish (Raphanus sativus L.) seeds

The present study was undertaken to determine the profile of the (n‐9) and (n‐7) isomers for C18:1, C20:1 and C22:1 fatty acids in radish seeds as well as their isomers. Radish (Raphanus sativus L. cvs. ‘Antep, Beyaz, Cherry Belle and Iri K?rm?z?’) seeds were produced in 2003–2005 from different sowing dates (SD). The n‐7 isomers of C18:1, C20:1 and C22:1 ranged from 0.7 to 1.3, 0.1 to 0.3 and 0.4 to 1.1 %, respectively. The average values of C18:1(n‐7) was highest (1 %) amongst the three acids. The ratios of (n‐7)/(n‐9) ranged from 4.5 % (‘Cherry Belle’, SD‐I) to 8.3 % (‘Antep’, SD‐III), 0.8 % (‘Iri K?rm?z?’, SD‐II) to 3 % (‘Iri K?rm?z?’, SD‐I) and 1.6 % (‘Cherry Belle’, SD‐I) to 3.7 % (‘Iri K?rm?z?’, SD‐I) for C18:1, C20:1 and C22:1. Erucic acid was the principal fatty acid with concentrations of nearly 34–39 % in ‘Antep’, 32–34 % in ‘Cherry Belle’, 30–33 % in ‘Beyaz’ and 21–22 % in ‘Ir? K?rm?z?’. The oleic acid content was higher in SD‐I and SD‐II than SD‐III in all cultivars. Correlation studies revealed that palmitoleic acid (C16:1) had a significant relationship between most of the fatty acids of the (n‐7)/(n‐9) family. The results indicated that palmitoleic acid is important in the synthesis of long‐chain fatty acids and that the data for the (n‐7)/(n‐9) ratios for C22:1 could be used as biochemical markers to determine the similarities or differences between radish cultivars.     

Synthesis of 6-hydroxy δ-lactones and 5,6-dihydroxy eicosanoic/docosanoic acids from meadowfoam fatty acids via a lipase-mediated self-epoxidation

Meadowfoam fatty acids were reacted with hydrogen peroxide in a lipase-catalyzed autocatalytic system, forming a mixture of 5,6-epoxyeicosanoic, 13,14-epoxydocosanoic, 5,6-epoxydocosanoic, and 5,6-13,14-diepoxydocosanoic acids in 98% yield. The 5,6-epoxy acids were cyclized to 6-hydroxy δ-eicosanoic/docosanoic lactones by sulfuric acid catalysis in high yield (99%). 5,6-Dihydroxy acids could be obtained from 6-hydroxy δ-lactones by a simple alkaline work-up procedure. Meadowfoam fatty acids were converted (77% yield) in a one-pot reaction to 6-hydroxy δ-lactones by in situ performic acid epoxidation and subsequent addition of sulfuric acid.